Project description:CarD is essential transcription factors in mycobacteria. For ChIP-seq, we used Mycobacterium smegmatis strains with CarD-FLAG (LK2539), where an additional copy of CarD under anhydrotetracycline inducible promoter was stably inserted into the genome. CarD-FLAG was expressed in exponential phase and ChIP performed at mid-exponential phase of growth.
Project description:RbpA is an essential transcription factors in mycobacteria. For ChIP-seq, we used Mycobacterium smegmatis strains with RbpA-FLAG (LK2541), where an additional copy of RbpA under anhydrotetracycline inducible promoter was stably inserted into the genome. RbpA-FLAG was expressed in exponential phase and ChIP performed at mid-exponential phase of growth.
Project description:CsrL (MSMEG_5890) associates with CarD and RNA polymerase in mycobacteria. For ChIP-seq, we used Mycobacterium smegmatis strain with CrsL (LK3051), where an additional copy of CrsL under anhydrotetracycline inducible promoter was stably inserted into M. smegmatis genome. CrsL-FLAG was expressed in exponential phase and ChIP performed at mid-exponential phase of growth.
Project description:Bacterial nucleoid-associated proteins play important roles in chromosome organization and global gene regulation. We find that Lsr2 of Mycobacterium tuberculosis is a novel nucleoid-associated protein that specifically binds AT-rich regions of the genome, including regions encoding major virulence factors, such as the ESX secretion systems, the lipid virulence factors PDIM/PGL, and the PE/PPE families of antigenic proteins. Comparison of genome-wide binding data with expression data indicates that Lsr2 binding results in transcriptional repression. Domain swamping experiments demonstrate that Lsr2 has an N-terminal dimerization domain and a C-terminal DNA binding domain. NMR analysis of the DNA binding domain of Lsr2 and its interaction with DNA reveals a novel structure and a unique mechanism that enables Lsr2 to discriminately target AT-rich sequences through interactions with the minor groove of DNA. Taken together, we provide evidence that mycobacteria have employed a structurally distinct molecule with an apparently different DNA recognition mechanism to achieve an equivalent function as the Enterobacteriaceae H-NS, coordinating global gene regulation and virulence in this group of medically important bacteria.